Valve mechanism for hoisting-engines.



S. T. NELSON. VALVE MECHANISM FOR. HOISTING ENGINES.

APPLICATION FILED SEPT. 8, 1908. RENEWED DEC. 21, 1911. 1,034,025. Patented July 30,1912.

4 SHEETS*SHEET 1.

COLUMBIA PLANOORAPH CO.,\VASHINGTON, D. c.

S. T. NELSON.

VALVE MECHANISM FOR HOISTING ENGINES.

APPLICATION FILED SEPT. B, 1908. RENEWED D150. 21, 1911.

Patented July 30, 1912.

4 SHEETS-SHEET 2.

S. T. NELSON. VALVE MECHANISM FOR HOISTING ENGINES.

IGATION FILED SEPT. B, 1908. RENEWED DEC.21,1911.

Patented July 80, 1912.

4 SHBETS-SHEET 3.

commnm PLANOGRAPM co., WASHINGTON 04 c S. T. NELSON. VALVE MECHANISM FOR. HOISTING ENGINES. APPLICATION FILED SBPT.B,1908. RENEWED DEG.21,1911.

1,034,025, Patented July 30, 1912.

4 SHEETSSHEET 4.

.ing engine mustbe operated.

UNITED sTATEs PATENT OFFICE.

SVEN T. NELSON, OF CHICAGO, ILLINOIS, ASSIGNOBn T0 SULLIVANMACHINERY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION.

VALVE MECHANISM FOR HOISTING-ENG-INES.

1. ,O34htl25.

Application filed September 8, 1908, Serial No. 452,104. Renewed December 21, 1911.

To all whom it may concern:

Be it known that I, SvEN T. NELSON, a citizen of the United States, and a resident of Chicago, county of Cook, and State of. Illinois, have invented certaln newiand use ful Improvements in Valve Mechanisnr for HoistingEngines, of which the following is a specification.

The invention relates to valvemechanism for hoisting or like engines which. must be frequently started and stopped, and which must do the greatest amount of work in starting the load. For. economical operation, a hoisting engineshouldbe provided with valve mechanism that will admit steam for nearly the full length of thestrokeof the engine piston when the engine is doing its greatest amount of work in starting the load. the desired speed acquired, the valve mechanism should be arranged to reduce the cutoff to about one-fourth of the stroke, so that the steam may be economically utilized by expansion of the engine cylinder. Hoisting engines employed for heavy work. such as operating the cages or skips in the shafts of mines, are usually of the expensive, Corliss type in which the valve mechanism can be effectively controlled by the governor, so that the engine will take steam for the greater part of its stroke when slowly starting and the cut-off will be shortened when the desired speed is attained to thereby effect economical operation of the engine. Such engines are quite. expensive and the slide valve mechanism of cheaper engines cannot be readily governor-controlled in this way.

The present invention seeks to provide simple and effective adjustable cut-off mechanism for a slide-valve engine so that it can take steam for nearly the full length of its stroke when starting and the point of cut-off be reduced when the desired speed is attained, and thereby adapt the cheaper slide-valve type of engine to meet the varying conditions under which a hoist- The invention also seeks to provide means whereby the engineer can simultaneously control the a dj ustable.cutoif mechanism and the throttle-valve of the engine with asingle handlever or shifter.

The invention consists in the features of construction, combinations Specification of Letters Patent.

When the load is well started and.

and arrange- Patented July 30, 1912.

Serial No. 667,209.

ments of parts hereinafter set forth, illustrated in the accompanying drawings and more particularly pointed out in the appended claims.

In the drawings, Figure 1 is a view in elevation of a slide-valve engine with the present invention applied thereto. Fig. 2 is a plan view of the same. Fig. 3 is a view .in elevation 011 an enlarged scale of the alve mechanism with the coverof the valve chest removed and certain partsshown. in central, vertical section. Fig. 4 is aview in. central, horizontal section of the parts shown in Fig. 3. i Fig. 5 is a detail section on line 5-5 of Fig. 4. Fig. 6 is a view similar to Fig. 3 illustrating a modification the engine by a piston-rod 18. The valve chest 19 of the engine is arranged on one side of the cylinder and is provided with a suitable seat 20 for a reciprocating slide valve 21. Steam passages as usual, lead from the valve seat to the opposite ends of the engine cylinder 11 and an exhaust passage 23 opens through the valve seat between the ends of the steam passages 22. The slide-valve 21 is provided as usual with inlet ports 24L and an exhaust cavity 25 for controlling the flow of steam to and from itheopposite ends of the engine cylinder 11.

A valve-rod 26 connected to the main slide valvev 21, extends through a stuffing-box 2'7 in the end wall of the valve chest and is connected to. a slide 28 that is guided in a suitable box 29 on the side of the engine frame. The forward end of the slide 28 (see Figs. 1 and 2) is connected by a link 30 to the inner arm 31 of the rocker 32. The rocker 32 is mounted on a shaft 33carried by a bracket 34: on the side of the engine frame. .The outer arm 35 of the rocker is connected by a pin 36 to a block 37 that is engaged by a link 38. A pair of eccentrics 39 on the engine shaft 13 are connected by eccentric strapstO and rods 41 tothe opposite ends ofthe link 38. A cross-piece 42 on the face of the link is provided with a projecting pin 43 by which the link is connected to the reversing lever. This reversible valve mechanism is of the well-known Stephenson link type and need not be more fully described. Other forms of reversible valve mechanism may be employed without departure from the essentials of the invention.

The main slide-valve is provided at its side edges with outwardly-projecting lugs 44 (see Fig. 3) which carry a balancing plate 45 (see Fig. 4) that is seated within a slide 46. The latter moves upon a suitable seat formed on the valve chest cover 47. A throttle-valve casing 48 is mounted upon the valve chest 19 and communicates therewith, as shown in Fig. 3. A suitable throttle valve 49 arranged Within the casing, is provided with a stem 50 that projects through a suitable stuffing-box 51, and is connected to an operating crank-arm 52. The crankarm 52 is fixed to a short, horizontal shaft 53 journaled in lugs 54 that project from the throttle valve casing. An arm 55 on the shaft 53 is connected by a rod 56 to an arm 57 on a shaft 58. This shaft is journaled in suit-able brackets 59 and is provided with an operating hand-lever or shifter 60 by which the operator may open and close the throttle valve 49 to admit a supply of steam to the engine valve chest or cut it off therefrom and thus start and stop the engine.

An auxiliary cut-ofi' valve of the Meyer type is employed in connection with the main slide-valve 21. This auxiliary cutoff valve comprises two sections 61 and 62 arranged on the back of the main slide-valve and between it and the balancing plate 45. A tubular valve-rod 63 extends through a stufling-box 64 in the end of the valve chest and its end portion extends through an opening in a lug on the auxiliary valve section 61. Nuts 65 are threaded upon the tubular valve-rod on opposite sides of the valve section 61 and securely connect the latter to the rod. The outer end of the tubular valve-rod 63 is provided with a stufling-box 66 and an inner, solid valve-rod 68 extends through the stuffing-box and through the tubular valve-rod and also through a perforated lug on the back of the auxiliary valve section 62. Nuts 69 are threaded upon a screw portion 7 O of the valve-rod 68 on opposite sides of the lug on the back of the valve section 62, and securely connect the valve section to the rod. The inner end of the valve-rod 68 extends within a sleeve 71 that is secured in position within an opening in the end wall of the valve chest 19. An upwardly projecting clip 72 is adjust-ably threaded upon the outer en of the tubular v valve-rod 63 and is held in place thereon by a lock-nut 73. A downwardly projecting clip 74 (see Fig. 5) is adjustably threaded upon the outer end of the solid valve-rod 68 and is secured in position thereon by a lock-out 7 The clips 72 and 7 4 are respectively connected by links 76 and 77 to the oppositely disposed arms of a T-shaped lever 78. This lever is pivotally connected by a pin 79 to the end of a reciprocating member or slide 80 arranged in guideways in the box 29. A pin 81 on the slide 80 projects outwardly through a slot 82 in the face of the box 29 and is connected by a rod 83 to an eccentric strap 84 (see Fi g. 2) which engages a third eccentric on the engine shaft 13. By this means, the slide 80 and the valve-rods 63 and 68 connected thereto through the medium of the lever 78 and links 76 and 77 are reciprocated to reciprocate the auxiliary valve sections 61 and 62 that control the inlet ports 24 of the main slide-valve 21 and determine the point of cut-off. By rocking the T-shaped lever 78 about its pivot-pin 79, the alve-rods 63 and 68 and the auxiliary valve sections 61 and 62 can be adjusted relatively to the operating means therefor and the valve sections moved to and from each other to vary the point of cut-off. The outer end of the valve-rod 68 is guided within an opening 85 (see Fig. 5) in the end of the slide 80 and within which it slides when the T-lever 78 is rocked upon its pivot 7 9.

The adjustment of the auxiliary valvesections 61 and 62 is preferably effected by an auxiliary motor comprising a small engine cylinder 86 which is mounted upon the frame 10 of the engine. A piston 87 within the auxiliary cylinder 86 is connected by a piston-rod 88 and a link 89 to the upwardly projecting arm of a shifter or bell-crank 90. This shifter or bell-crank is pivotal1ymouuted upon a bracket 91 and its horizontal arm is connected by a pivot pin 92 to the lower end of a link 93. The upper end of the link 93 is connected by a pivot pin 94 to the central, horizontal arm of the T-lever 78. A slide-valve 95 within the steam chest 96 of the auxiliary cylinder 86 controls the steam and exhaust ports 97 and 98 and the flow of steam or other motive fluid under pressure through said ports and to and from the opposite ends of the cylinder. Means are provided whereby the operator may manually shift the valve 95 to admit steam to either end of the auxiliary cylinder 86 and thereby shift the piston 87 to one or the other end of this movement. When the valve 95 is in the position shown in the drawings, the piston 87 will be held against the right-hand end or head of the auxiliary cylinder 86 and the T-shaped arm will. be held by the connections between it and the piston 87 in such a position that the auxiliary valve sections 61 and 62 are close together. The flow of steam through the inlet ports 24 of the main slide-valve, in this position of the parts,v will not be cut: oif by the auxiliary valve sections until-the engine piston 17 is near the end of its stroke. In starting the to the right-hand end of the auxiliary cylinder 86, so that the piston 88 will be moved to the left-hand end of the cylinder. This movement of the piston will rock the T- lever 78 upon its pivot 79 and thereby shift the valve-rods 63 and 68 and move the auxiliary valve sections 61 and-62 apart and-the flow of steam to the engine cylinder 11 will then be cut off at about one-quarterstroke, so that the steam will be economically utilized by expansion in the cylinder. In either position of the piston, the bell-crank 90 is of course held against substantial movement. The link 93, however, will rock back and forth upon the pivot pin 92 as the slide 80 and parts connected thereto are reciprocated.

The ends or heads of the small auxiliary cylinder 86 act as stops to limit the movement of the piston 88 and therelative adjustment of the auxiliary valve sections 61 and 62. The position of the auxiliary valve sections at the limits of their relative adjustment, maybe varied as desired by adjusting the valverods 63 and 68 relatively to the clips 72 and 7 1 by which the rods are connected to the links 76 and 77 of the valve shifting devices. The shifter or hand-lever 60 which controls the throttle valve is also preferably arranged to control the. adjusting means for the auxiliary valve sections 61 and 62. For this purpose, the shaft 58 is provided with an upwardly projecting arm 99 which is connected to the rear end of a rod 100. The forward end of the rod is provided with an elongated slot 101 which engages a pin 102 upon the lower end of an arm 103. The upper end of this arm is connected to a short shaft 104 that is journaled on a bracket 105 projecting from the auxiliary cylinder 86. A short crank-arm 106 upon the inner end of the shaft 104: is connected by a link 107 to the stem 108 of the valve 95.

In the position of the hand-lever or shifter 1 60 shown in the drawings, the throttle-valve 49 is closed. To open the throttle valve the lever is moved in the direction indicated by the arrow in Fig. 8. In the closed position of the throttle valve the rod 100 that is connected to the throttle valve shifter, will hold the valve 95 of the auxiliary cylinder 86 in position to admit steam to the left-hand end .of the cylinder and hold the piston at the be started from any point.

right-handend of its movement, as shown,

.Wi-th: the auxiliary valve sections 61 and 62 near one another, so that the point of cutoff will be near the end of the stroke of the engine. Inthis position of the parts, the pin 102 on "the lever 108 will be at the left- :hand end of the slot 101 inthe rod 100.

This lostmotion connection between the arm 103 and the rod-102 permits a partial shiftof the lever or shifter 60-before the arm 103 is moved. In starting the engine, the operator will move the lever 60 through a portion of. its full movement to open the 'throttle valve 19 and admit steam to the steam chest 19. This part movement 'ofthe lever 60 will merely serve to take up the lostmotion between the rod 100 and the arm 1.03 so that the valve 95 and the piston 87 of the auxiliary engine will remain in position and the auxiliary cut-off valve sections 61 and62 will be so operated that the engine will take steam for nearly the full length of I its stroketo start theload. After the load is started and the work required of the engine reduced, the operator will complete the shift. of the lever 60 to fully open the throttle valve and thereby, through the medium of the rod 100 and arm 103, will shift the valve 95 to admit steam to the right-liand end of the auxiliary cylinder 86. The piston- 87w. therein will then be shifted to its left-hand end and the cutoff valve sections 61 and 62 will be movedapart so as to cut off the flow of steam to the inlet ports 24 of the main slide valve 21 when the engine piston has. traveled through about one-quarter of its stroke. When the operator shifts the lever 60 back to the position shown in the drawings to close the throttle valve and stop the engine, the valve 95 will be shifted so that v the piston 87 is moved back to the righthand end of the cylinder 86 and the auxiliary cutoff valve sections 60 and 61 are moved together so as to effect a long cut-off when the engine is again started. I It will be understood that, as usual in hoisting engines, there will be a pair of engines, one coupled to each end of the shaft 13 with their cranks arranged at an angle of ninety degrees to each other so that there i will be no dead center and the engines can The two engines will be duplicates of each other and the shaft58 will be connected to the throttle valve or valves and to the cut-off adjusting devices of both engines. The single handlever or shifter 60 on the shaft 58 will thus simultaneously control the operation of the two engines.

In the modification illustrated inF-ig. 6, the adjustable valve sections 61 and 62 are connected to two solid valve rods 109 and 110 which are arranged side by side and extend through two stufling-boxes 111 in the end Wall of the steam chest. The valve rods 109 and 110 extend through openings in lugs on the back of the valve sections 61 and 62. The valve rod 109 extends loosely through the lug on the valve section 62 but is secured to the valve section 61 by nuts 112 threaded on a screw portion 113 thereof on opposite sides of the valve section 61. In a similar manner, the valve rod 110 extends loosely through the lug on the back of the valve section 61 and is secured to the lug on the back of the valve section 62. A pair of clips 114- are adjust-ably threaded upon the outer ends of the valve rods 109 and 110 and are secured in position by lock-nuts 115. These clips are connected by links 116 to the upper and lower arms of the T-shaped lever 78. The opposite ends of the valve rods are guided in a sleeveor bushing 117 fixed to the outer end wall of the steam chest 19. The other parts are similar to those previ ously described and the operation is the same.

It is obvious that numerous changes may be made in the details set forth without departure from the essentials of the invention as defined in the claims.

I claim as my invention 1. In a hoisting engine, the combination with the engine cylinder, of a main valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sect-ions controlling the inlet ports of said main valve, separate valve rods connected to said auxiliary valve sections, means driven by the engine for operating said valve rods and said auxiliary valve sections, means for adjusting said rods and said valve sections to vary the point of cut-off, an auxiliary motor for throwing said adjusting means to the opposite ends of its movement, substantially as described.

2. In a hoisting engine, the combination with the engine cylinder, of a main valve therefor driven by the engine and having in let and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main valve, separate rods connected to said auxiliary valve sect-ions, a member driven by the engine for operating said rods and Valve sections, an auxiliary engine cylinder, a piston therein, means operated by said piston for shifting said rods to adjust said auxiliary valve sections to and from each other and a manually operated valve mechanism controlling the flow of motive fluid to and from said auxiliary cylinder to throw said piston and said adjusting means to the opposite ends of their movement, substantially as described.

3. In a hoisting engine, the combination with the engine cylinder, of a main valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, means driven by the engine for operating said rods and valve sections, a throttle valve for the engine, a shifter for said throttle valve, and means operated by said shifter for adjusting said rods and valve sections to vary the point of cut-off, substantially as described.

l. In a hoisting engine, the combination with the engine cylinder, of a main valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-oil valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, a member driven by the engine for operating said rods and valve sections, a. throttle valve for the engine, a shifter for said throttle valve, means operated by said shifter after a predetermined movement thereof for moving said rods relatively to said member to adjust said auxiliary valve sections to and from each other, substantially as described.

5. In a hoisting engine, the combination with the engine cylinder, a main valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary out-oil valve comprising two sections controlling the inletports of said main valve, separate valve rods connected to said sections,1neans driven by the engine for operating said rods and valve sections, an auxiliary motor, means operated by said auxiliary motor for adjusting said rods and. valve sections to vary the point of cut-oil, a throttle valve for the engine, a shifter for said throttle valve, and valve mechanism for said auxiliary motor controlled by said shifter, substantially as described.

6. In a hoisting engine, the combination with the engine cylinder, of a main valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-oil valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, a member driven by the engine for operating said rods and valve sections, an auxiliary engine cylinder, a piston in said cylinder, means operated by said piston for moving said valve rods relatively to said member to ad just said auxiliary valve sections to and from each other, a throttle valve for the main engine, a shifter for said throttle valve. valve mechanism controlling the flow of motor fluid to and from said auxiliary cylinder, and lost-motion connections between said valve mechanism and said shifter, substantially as described.

7. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor having inlet and exhaust ports, reversible valve mechanism driven by the engine for reciprocating said main slide valve, an auxiliary cut-off valve comprising two sectlons on the back of said main valve and controlling the inlet ports thereof, sepa rate valve rods connected to said sections, a member driven by the engine for reciprocating said rods and valve sections, an auxiliary engine cylinder, a piston therein, means operated by said piston for moving said valve rods relatively to said member to adjust said valve sections to and from each other, and manually operated valve mechanism controlling the flow of motor fluid to i tions, a member driven by the engine for reciprocating said. rods and valve sections, a throttle valve for the engine, a shifter for said throttle valve and means operated by said shifter after a predetermined movement thereof for shifting said rods relativelyto said member to adjust said auxiliary valve sections to and from each other, substan tially as described.

9. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor having inlet and exhaust ports, reversible valve mechanism driven by the engine for reciprocating said main slide valve, an auxiliary cutoff valve comprisingtwo sections on the back of said main valve and controlling the inlet ports thereof, separate valve rods connected to said sections, a member driven by the engine for reciprocating said rods and valve sect-ions, an auxiliary engine cylinder, a piston in said cylinder, means operatively connected to said piston for moving said rods relatively to said member to adjust said auxiliary valve sec tions to and from each other, a throttle valve for the main engine, a shifter for said throttle valve, valve mechanism for said auxiliary cylinder, and operating lost-motion connections between said shifter and said valve mechanism, substantially as described.

10. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections con-- trolling the inlet ports of sald main valve,

separate valve rods connected to said sections, a member driven by the engine for reciprocating said rods and valve sections, shiftable connections between said member and said valve rods, adjusting means for shifting said connections and valve rods to move said valve sections to and from each other, an auxiliary motor for operating said adjusting means, and manually operated devices controlling the operation of said motor to throw said adjusting means to the opposite ends of its movement, substantially as described.

11. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main slide valve, separate valve rods connected to said sections, a reciprocating member driven by the engine for operating said rods and valve sections, shiftable connections between said reciprocating member and said valve rods, adjusting means for shifting said connections and valve rods during the operation of the engine to move said valve sections to and from each other, an auxiliary engine cylinder, a piston in said cylinder operativelyconnected to said adjusting means, and manually operated valve mechanism controlling the flow of motor fluid to and from said auxiliary cylinder to throw said piston and said adjusting means to the opposite ends of their movement, substantially as described.

12. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, a reciprocating member driven by the engine for reciprocating said rods and auxiliary valve sections, shiftable connections between said reciprocating member and said valve rods, adjusting means for shifting said connections and valve rods during the operation of the engine to move said valve sections to and from each other, a throttle valve for the engine, a shifter for said throttle valve and operating connections between said shifter and said adjusting means, substantially as described.

13. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-oft valve comprising two sections controlling the inlet ports of said main slide valve, separate valve rods connected to said sections. a reciprocating member driven by the engine for reciprocating said rods and valve sections, shiftable connections between said reciprocating member and said valve rods. adjusting means for shifting said connections and valve rods during the operation of the engine to move said valve sections to and from each other, an auxiliary engine cylinder, a piston therein operatively connected to said adjusting means, a throttle valve for the main engine, a shifter for said throttle valve and valve mechanism for said auxiliary cylinder connected to said shifter, substantially as described.

14. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cutoff valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sec tions, a reciprocating member driven by the engine for reciprocating said valve rods and auxiliary valve sections, shiftable connections between said reciprocating member and said valve rods, and adjusting means for shift-ing said connections and valve rods during the operation of the engine to move said auxiliary sections to and from each other to vary the point of cut-off, said connections being adjustable independently of said adjusting means, to adjust said valve sections relatively to said adjusting means, substantially as described.

15. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-01f valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, a reciprocating member driven by the engine for reciprocating said rods and valve sections, shiftable connections between said reciprocating member and said valve rods, adjusting means for shifting said connections and valve rods during the operation of the engine to move said valve sections to and from each other, said shiftable connections being adjustable independently of said adjusting means to vary the position of said valve sections relatively to said adjusting means, a throttle valve for the engine, a shifter for said throttle valve and means actuated thereby for operating said adjusting means, substantially as described.

16. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main slide valve, separatevalve rods connected to said sections, a reciprocating member driven by the engine for reciprocating said rods and valve sections, shiftable connections between said member and said valve rods, adjusting means for shifting said connections and valve rods during the operation of the engine to move said valve sections to and from each other, means for adjusting said shiftable connections independently of said adjust-ing means to vary the position of said valve sections relative to said adjusting means, an auxiliary engine cylinder, a piston in said cylinder operatively connected to said adjusting means and manually operated valve mechanism for said auxiliary engine cylinder to throw said piston and said adjusting means to the opposite ends of their movement, substantially as described.

17 In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, a reciprocating member driven by the engine, a lever pivoted on said member and connected on opposite sides of its pivot to said valve rods, a shifter for moving said lever and valve rods during the operation of the engine to adjust said valve sections to and from each other, an auxiliary motor for operating said shifter and manually operated means controlling said auxiliary motor to throw said piston and said adjusting means to the opposite ends of their movement, substantially as described.

18. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor having inlet and exhaust ports, reversible valve mechanism driven by the engine for reciprocating said main slide valve, an auxiliary cut-off valve comprising two sections on the back of said main valve and controlling the inlet ports thereof, separate valve rods connected to said sections, a reciprocating member driven by the engine, a lever pivoted. to said member and connected on opposite sides of its pivot to said valve rods, a shifter for moving said lever and valve rods during the operation of the engine to adjust said valve sections to and from each other, an auxiliary engine cylinder, a piston in said cylinder oppositely connected to said shifter, valve mechanism controlling the flow of motor fluid to and from said auxiliary cylinder to throw said piston and said adjusting means to the opposite ends of their movement, and a hand-lever controlling said valve mechanism, substantially as described.

19. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said secti ons, a reciprocating member driven by the engine, a lever pivoted on said member and connected on opposite sides of its pivot to said valve rods, a shifter for moving said arm and said valve rods to adjust said auxiliary valve said sections to and from each other, a throttle valve for the engine, a lever for operating said throttle valve, and means operated by said throttle lever after a pre determined movement thereof for actuating said adjusting shifter, substantially as described.

20. In a hoisting engine, the combination with the engine cylinder, of a. main slide valve therefor driven by the engine and hav ing inlet and exhaust ports, an auxiliary cutoif valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, a reciprocating member driven by the engine, a lever pivot-ed on said member and connected on opposite sides of its pivot to said valve rods, a shifter for moving said lever and valve rods to adjust said valve sections to and from each other, an auxiliary engine cylinder, a piston therein operatively connected to said shifter, a throttle valve for the main engine, an operating lever for said throttle valve, valve mechanism for said auxiliary cylinder, and operating, lost-motion connections between said valve mechanism and said throttle lever, substantially as described.

21. In a hoisting engine, the combination with the engine cylinder, of a main slide valve therefor driven by the engine having inlet and exhaust ports, an auxiliary cut-off valve comprising two sections controlling the inlet ports of said main valve, separate valve rods connected to said sections, a reciprocating member driven by the engine, a lever pivoted between its ends upon said reciprocating member, adjustable connections between the opposite ends of said lever and said valve rods, a shifter for said lever and a link connecting said shifter and said lever, substantially as described.

22. Ina hoisting engine, the combination with the engine cylinder, of a main valve therefor driven by the engine and having inlet and exhaust ports, an auxiliary cut-off valve comprising two sect-ions controlling the inlet ports of said main valve, a tubular valve rod connected to one of said valve sections, a second valve rod connected to the other section and extending through said tubular valve rod, a member driven by the engine for reciprocating said rods and valve sections, adjust-able connections between said member and said valve rods and means for shifting said connections and rods to adjust said auxiliary valve sections and vary the point of cut-off, substantially as described.

SVEN T. NELSON. Witnesses:

HARRY L. CLAPP, CLARA A. NORTON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. i 

